1. Field of the Invention
The present invention relates to a display device and a television device each having a light emitting element.
The invention further relates to an electronic device that uses a display device having a light emitting element.
2. Description of the Related Art
In recent years, a display device having a light emitting element typified by an EL (Electroluminescence) element has been actively developed, and it is expected to be widely used by taking advantages of the light emitting element such as high image quality, wide viewing angle, and reduced thickness and weight.
The light emitting element has the characteristic that its resistance (internal resistance) varies with the surrounding temperature (hereinafter referred to as ambient temperature). Specifically, the resistance decreases when the temperature is more than room temperature, while the resistance increases when the temperature is less than room temperature. Such a characteristic of the light emitting element is shown in a graph of FIG. 10A showing the relation between voltage-current characteristics of the light emitting element and temperature. The light emitting element also has the characteristic that its current decreases with time. Such a characteristic of the light emitting element is shown in a graph of FIG. 10B showing the relation between voltage-current characteristics of the light emitting element and time.